As set forth, for example, in Patent Document 1 (Japanese Patent Unexamined Publication No. 2009-97172), some of the conventional flush toilets flushed with flush water supplied from a flush water source to discharge waste have, in order to increase visibility of the inner rim wall surface, the inner rim wall surface that is sloped outward from the bottom thereof toward the top thereof, or the inner rim wall surface that rises vertically.
As set forth in Patent Document 1, some of the conventional flush toilets also include the inner rim wall surface that is sloped inward from the bottom thereof toward the top thereof.
Also, as set forth in Patent Document 2 (Japanese Patent Publication No. 3381261 (WO 98/16696)), some of the conventional flush toilets include an overhang structure formed throughout the circumference of the inner wall surface of the rim, or an overhang structure formed only in a portion of the inner wall surface of the rim.
However, since the above-described conventional flush toilets have the inner rim wall surface that is sloped outward from the bottom thereof toward the top thereof or the inner rim surface that rises vertically, if a shelf is formed to cause flush water to circulate on the top edge of the bowl waste receiving surface on the flush toilets, the shelf is exposed to a user standing in front of and above the bowl.
This causes a perceptional problem in users that the users may experience a discomfort by seeing waste adhered to the shelf, and also would aesthetically degrade the appearance of the toilet.
The conventional flush toilets formed with a large overhang structure throughout the circumference of the inner wall surface of the rim have problems that the inner wall surface of the rim loses its visibility to a large extent, resulting in making clean-up work difficult.